Mowing machine



Dec. 29

H. SCHIEFERSTEIN MOWING MACHINE Filed March ,1 1923 Patented Dec. 29, 1925.

warren STATES I-IEINIEZiICliiI SCHIEFEBSTEIN, OF BERLIN-CI-IARLOTTENBURG, GERMANY.

MOWING MACHINE.

Application filed. March 1, 1923v Serial No. 622,161.

To all w/zom it may concern:

lie it known that I, HEINRICH Scrnnrnns'rniN, a citizen of the German Republic, residing at Ber]in-Charlottenburg, Kaiser- Friedrichstrasse 1, Germany, have invented certain new and useful Improvements in Mowing Machines, of which the following is a specification.

This invention has reference to improve- .ments in mowing machines, and it particularly refers to means for reducing the strain, due to the oscillatory motion, on the operating parts of the machine in a novel manner, and it is also intended to generally improve and to simplify the construction and operation of machinery of the kind referred to. in the operating means heretofore known and used in connection with mowing machines the crank pin is compelled to impart kinetic energy to the knifeor knives at the beginning of each stroke, while it must absorb any excess of kinetic energy before the termination of the stroke, such excess being destroyed in the form of friction. In such construction the consumption of energy of the machine is greatly increased, and the crank pin is frequently heated beyond the admissible limit In view of these difficulties this invention operates on the principle of imparting oscillating movement to the knife or knives of the mowing machine by a mechanical oscillatory system, thereby supplying only that energy by the crank which .is actually consumed in the operation of the machine.

The invention will be more fully described with reference to the accompanying drawing showing by way of example and in a diagrammatic manner the main operating portions of a mowing machine partly in elevation and partly in section. Upon the relatively stationary bar or thill (Z of the machine shown in cross section in the drawing a strong spring 3 is adjustably mounted. Near the bottom end of said spring the knife in is articulated by the intermediary of a link Z) on a corresponding knife bar. Upon mlling this spring 8 laterally and then releasing it the spring causes the knife to be reciprocated several times with a definite period of reciprocation, whereupon the system returns to its position of rest. The definite number of oscillations performed by this system, constituted by knife m, link I; and spring e per second is called 0S illation frequency of the oscillatable system constituted by the mass of the knife, its link, if a link he used, and the spring. The oscillation frequency of the system is selected so as to cause it to approximately agree with the. normal number of operating revolutions. By the displacement of the spring 8 at its point of attachment or by displacing or altering the weight mounted on the spring, which, if desired, may be entirely dispensed with, the oscillation frequency may be varied, whenever required.

To the storage or accumulating spring 8 fastened the auxiliary or coupling spring Z r the operative length of which may likewise be varied by displacement within the fastening member 72 The coupling spring 7: is connected by means of the pitman rod a to the crank wheel 9, and it is guided by the link Upon now rotating the crank wheel the coupling spring is produces tensional forces of varying directions at its point of attachment in consequence of which the oscillatory system a b, m commences to be oscillated, and this the more in proportion as the number of revolutions of the crank per, unit of time approximates the oscillation frequency of the oscillating system. The inertia of the reciprocating oscillating knife is converted in the terminal positions into potential energy in the energy storing spring 8, and is always restored after the reversal of the direction of movement. The crank pin merely supplies and makes up for the consumed efficient output. It has been shown by experiments that the tractional force required is considerably less than that necessitated with machines of that type as heretofore constructed, and that the crank pin remains perfectly cool. The oscillating 9 system is preferably entirely or approximately in tune with the rotating crank Wheel.

It is evident that one or the other of the resilient or elastic members may be shaped so as to constitute a spiral spring, or it may be constructed similar to a railroad buffer spring. It is also to be understood that my invention is susceptible of various other modifications and constructional alterations as the changing conditions of its application and the convenience of the operator may demand, and without departing from the spirit of my invention as pointed out in the claims,

I claim 1. In a mowing anachine, the combination with oscillating parts; of a resilient'energy storing member operatively connected therewith and constituting an oscillatory system of definite oscillatory frequency, and means to drive said system substantially in synchronism with such frequency, and a resilient member connecting the oscillatory system and the driving means. 2. In a mowing machine, the combination with oscillating parts including a cutter blade, .a rotating crank and V a resilient connecting; member; of resilient storing means for drivingsaid oscillating parts and driven by said crank, said crank operating said resilient connecting member and the resilient connecting member operating said oscillating parts in synchronism with the frequency ,p ericd of said resilient storing means and oscillating parts.

.3. In a mowingmachine, the combination with oscillating parts including a cutter blade; of an energy storing spring operati-yely connected to said parts, means for -.oscill .ating said spring vvand parts substantially insynchronism with the oscillating period ,of said-spring andconnected ,parts, and a resilient connection between the spring and operating means.

4:. in a mowing 1 achine, the combination with oscillating parts, resilient member ,operatiyely connected therewith and constilt-nting an o cillatory system ot'xdefinite oscillatorytreqnency of means to drivesaid system substantially in synchronism with such ,lirequency, a resilient .niember connecting the means ,to adjust the elasticity of said resilientmember,

In ,a mowing machine, a relatively sta= t'io-nany .ineniber, ta "spring secured to said membe a reciprocable mower knit'e con- ,nected evith said spring, a crank, and a re- M lririf g connection :between vvthe crank and spring. v y

6, 1n niowing nachine, a relatively stastionar-ymember, .a spring secured thereto, a -.cutt er connected to, the spring, :a resilient member connected to the-spring, and .reiciprocating mechanism connected -to the resilient member.

7. In a mowing machine, a relatively stationary memher a spring secured thereto, .a reciprocating cutter connected with said SPIi-HQ, ,a reciprocating driving mechanism latory system and (the driven means and r cutter connected to the spring, a resilient member connected to the spring; and reciprocati mechanism connected to the resilient member, and means to adjust the vibrations of the spring substantially in synchronism with the movements of said mechanism.

10. Ina mowing machine,.a relatively sta- .tionary member, a spring adjustably connected :at oneend to said member, a reciprocatinc' cutter connected to the other end of said 'eciprocating motion, and an auxiliarr; mg connectedto the driving mechanismfland adiustably connected to the first sprin 11. In a mowing machine, a relatively sta tionary member, a spring connected at one end to said member, reciprocating cutter ..connceted to .the other end of said spring, a mechanism for imparting reciprocating motion,comprising a crank and a pitn ian rod, said rod operatirely connected at one end to 'd crank, a link suspending theother end c-t' said rod .and an auxiliary spring); connected atone end to said firstsprinc' and-at itsother end tosaid rod.

12. Ina-n'1o\v.in, ;-machinesv relatively sta- :ti;onar y member, ;a spring adjustably connected.atoneendtosaid member, a reciprocating 'cnttersconnected to the other end. of saidspring, means to ad ust the frequency of Nihrationofsaid s )rinc' a mechanism for imparting reciprocating motion, comprising a crank and a ,pitman rod, said rod operatively connected at :one end to said crank, .a link'snspending the other end of said rod, and auxiliary spring adjnstahly connected atone end to said first spring and at its otherendto said rod. 1

"in testimony whereof, I eafiix my signature.

HEINRICH SGHIEFERS IN- spring, a driving mechanism for im-' 

